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CONTENTS
Page
INTRODUCTION................. ............................... 3
PLANTING QUALITY AND PERFORMANCE ......................... 4
ROOT SYSTEM DEVELOPMENT AND PERFORMANCE ............... 5
PLANTER PRODUCTIVITY CONSIDERATIONS................................6
LITERATURE CITED ............................................................. 7
FIRST PRINTING 3M, JULY 1991
EDITOR'S NOTE: Previous issues in this series were listed as
Forestry Departmental Series. Beginning with this issue, subse-
qjuent issues will he identified as School of Forestry Series to
reflect current organization at Auburn University.
Infonnmation contained herein is available to all without
regard to race, color, sex, or national origin.
PLANTING MORPHOLOGICALLY
IMPROVED SEEDLINGS
WITH SHOVELS'
JOHN I. BIAKE and DAVID B. SOUTH
2
INTRODUCTION
IN SPITE OF the fact that shovels are commonly used to
"operationally" plant seedlings on the West Coast, their use in
the South presently is confined mostly to a few researchers and
consultants who choose to plant morphologically improved
seedlings
3
. Annually, several thousand planting shovels are sold
in the Pacific Northwest while less than 100 are sold 
in the
South. The technique used with planting shovels has been
described by Wickman (38) and is illustrated in figure 1. The
planting shovel referred to in this publication is the long handle
planting shovel (TT 2-0) that has been reinforced with a gusset
along the backspine of the blade (the blade is 12 inches long
and either 5.5 or 6.5 inches wide). The objective of this publica-
tion is to discuss how planting with shovels might improve
seedling performance when used in conjunction with southern
pine seedlings with large root systems. Planting morphological-
ly improved seedlings with large root systems can result 
in bet-
ter survival and growth of southern pine plantations (23).
However, successful tree planting operations are not solely
dependent on use of morphologically improved seedlings. It is
critical to choose an appropriate set of planting specifications
(how seedlings should be placed in the soil) and a system for
insuring that the specifications are achieved by the planters
(appropriate equipment, quality control inspections, incentives
and/or penalties). Unfortunately, many landowners overlook
the importance of these elements and over-emphasize superfi-
cial methods (e.g. machine planting vs. hand planting), or con-
sider the cost of the operation and not the cost per surviving
tree. However, selecting appropriate equipment does help to
achieve the planting specifications in a cost-effective manner.
The objective should be to develop a system which insures a
consistently high success rate across the range of expected
planting environments. A target level of 90 to 95 percent sur-
vival is not unreasonable, even for operational plantings.
'The authors express appreciation to James M. Vardaman for his support
and manuscript review, to Plum Creek Timber Company for making available
seedling survival and tree planting production data, to Weyerhaeuser Company
for providing the cover photo, and to Tree Farmer magazine for the color sepa-
rations for printing.
Respectively, Research Ecologist, USDA Forest Service and Associate
Professor, School of Forestry.
3
Bareroot loblolly pine (Pinus taeda L.), slash pine (Pinus elliottii Engelm.),
and shortleaf pine (Pinus echinata Mill.) seedlings that are grown in the nurs-
ery at low seedbed densities (_ 20 per square foot) are said to be "morphologi-
cally improved" if they are: (1) larger in diameter (half or more of the plantable
seedlings have root-collar diameters greater than 5 millimeters); (2) have a larg-
er root volume (median value > 3 cubic centimeters); (3) have a higher root
weight ratio; (4) have been cultured to have more fibrous roots; and (5) are not
taller than seedlings raised at higher seedbed densities. Grade 1 seedlings are
not "morphologically improved" when grown at high seedbed densities. This is
because they may be taller and may have a lower root weight ratio than Grade 2
seedlings.
Operational data from a case study in the Pacific Northwest
can be used to illustrate how survival can be increased by
improving various regeneration methods. Due to poor seedling
survival in the early 1970's, various steps were taken to increase
regeneration success. Better planting supervision began in
1975 and as a result, survival was improved markedly, as shown
in figure 2. After 1978, survival was again enhanced by using
morphologically improved stock, controlling competing vegeta-
tion, and improving planting and handling techniques. As a
result of consistent survival, initial planting level was reduced
from over 600 to fewer than 350 trees per acre. The integration
of these practices resulted in reducing the cost of seedling
establishment (1967 dollars) by more than half, as shown in fig-
ure 3.
1. With shovel turned backwards, work the shovel into the soil.
2. Push shovel away from you to break the soil.
3. Lift and pull shovel back slightly to hold soil away from hole.
4. Place tree in hole, with root collar approximately 4 to 5 inches below the
soil surface.
5. Pull shovel away to allow soil to fall back against the roots and lift seedling
slightly so that root collar is approximately 3 to 4 inches below the soil surface.
6. Pack soil tightly around roots.
FIG. 1. Technique used when planting with shovels (38).
4
, I 1 V ~ " "
of~. the,
5
5 morphoo~gic1/
FIG. 2. The average survival and stocking of one forest unit in cen-
tral Washington (1970-1989).
1970 1975 1980 1985 1990
Year of planting
FIG. 3. The cost of establishment on a per acre and per surviving
tree basis for one forest unit in central Washington (1970-1989).
PLANTING QUALITY AND PERFORMANCE
When planting quality is discussed among experienced indi-
viduals, most agree on the traits that they consider desirable in
terms of depth, root placement, packing, etc. What is not
always agreed upon is a minimum acceptable standard for
these traits. For example, how tight does the soil need to be
packed around the roots or how deep should the seedlings be
planted? As the planting environment becomes more adverse,
more stringent requirements are needed to achieve a given
level of seedling performance.
Because it is difficult to treat planting "quality" in a quantita-
tive manner for all but a few traits, researchers tend to avoid
the problem. As a result "planting quality," in practice, be-
comes an elusive personal or organizational standard. However,
as table 1 shows, careful planting technique makes a difference.
Unfortunately, it is not known which "careful" techniques led
to the observed increases in survival.
In some cases specific techniques are known to influence
survival. For example, in recent trials with loblolly pine, placing
the upper portion of the root system 3-5 inches below the soil
surface increased survival by 5 to 15 percent, table 2, relative to
placing the top of the root system only one-half to 2 inches
below the soil surface. Loosely planted seedlings also have a
very poor chance for survival. Shiver et al. (32) reported a 26
percent decrease in survival between firm and loose planted
loblolly pine seedlings in the Georgia Piedmont. There is little
published information on how planting techniques might influ-
ence tree growth. Deeper planting does appear to result in
greater initial height growth, sufficient at least enough to offset
the initial reduction in height after planting. In general, mini-
mizing root distortions of southern pines during planting (twist-
ing, balling-up, J-rooting, L-rooting, U-rooting) does not
appear to improve either survival or height growth (37,9,36,18,
12,22,14,39,30,31). In fact, when planting a 6-inch-long root in
a 5-inch hole, planting the seedling deep with a J-root can
increase survival when compared to keeping the root straight
and planting the seedling too shallow (6). Although windthrow
due to root distortion can occur on poorly drained soils in the
South (16), it appears to be more of a problem in windy cli-
mates such as New Zealand (21).
Where differences in seedling performance among planting
techniques or equipment have been reported (e.g. 26,30), it is
rarely stated what specific factors affected performance.
Differences observed may be confounded by the site condi-
tions or the failure of individuals to use equipment properly.
How, then, might one expect the use of shovels to influence
planting quality and subsequent field performance? The main
advantages of shovel planting compared to hoedads or dibble
TABLE 1. IMPROVEMENTS IN LOBLOLLY PINE SURVIVAL FROM CAREFUL HAND
PLANTING TECHNIQUES COMPARED TO OPERATIONAL PLANTING
Pct. survival
Careful hand plant Operational plant Pct. gain
Muller (25):
1
Company Crews..... .... 92.0 87.0 (H)
4  
+ 5.0
Company Crews..... .... 92.0 88.0 (M) + 4.0
Contract Crew ...... ..... 93.0 81.0 (H) +12.0
Rowan (28):
1979-80 .......... .................. 46.1 32.0 (M ) +14.1
1980-81....................... ........... 87.2 52.5 (M ) +34.7
Senior & Hassan (30):2
1981-82.................................... 87.0 74.0 (H) +13.0
1982-83.................................... 95.0 91.0 (H) + 4.0
1981-82.................................... 77.0 73.5 (M) + 3.5
1982-83.................................... 88.0 86.3 (M) + 1.7
Shiver et al. (32):
3
1986-87.................................... 87.8 75.1 (H & M) + 12.7
1987-88.................................... 92.2 84.8 (H & M) + 7.4
'A number of plots remeasured by Muller in 1986 showed a larger range 
in
survival differences (+6 to +22 percent).
2
Senior and Hassan recorded unusually high rainfall after planting in both
years. They believed it alleviated differences i plantin quality
3
Survival differences among units ranged from 0 to + 0 percent.
4
M = Machine planting; H = Hand plant with dibble bar or hoedad.
TABLE 2. EFFECT OF PLANTING DEPTH ON LOBLOLLY PINE SEEDLING SURVIVAL
FROM FOUR NURSERIES (PROVIDENCE FORGE, VA. (8), MUNSON, FLA.,
WAYNESBORO, MISS., AND SUMMERVILLE, S.C.)
Location % Survival Planting depth in inches
Deep Shallow Deep Shallow
Florida............................. 85 70 4.7 1.9
Mississippi ....................... 84 69 3.7 0.5
South Carolina......... 82 79 6.5 4.7
Virginia ...................... .. 87 82 3.0 1.0
bars is a deeper hole to accommodate placement of the roots
below the ground surface as well as a wider hole to facilitate
rapidly inserting fibrous lateral roots. Shovel planting also can
facilitate close root to soil contact, which is critical for adequate
water uptake by transplanted seedlings (29). It is known from
other planting tool trials (e.g. 24,13) that those tools which
enable development of the advantages noted above can
increase survival substantially on difficult sites. A great many
foresters and contractors in the Pacific Northwest have adopt-
ed shovels as a preferred planting tool for stock with large root
systems even though the root systems are routinely pruned to
between 6 and 7 inches. They believe it enables them to effec-
tively meet planting standards. A few organizations require
shovels as a matter of contract compliance.
ROOT SYSTEM DEVELOPMENT AND
PERFORMANCE
Increase in root system size was a factor stimulating the
adoption of shovels in other regions. Root development can be
measured in a number of ways, such as surface area, volume
displacement, and mass, or weight. A substantial amount of
field data has been accumulated for Douglas-fir (Pseudotsuga
menziesii (Mirb.) Franco), western hemlock (Tsuga hetero-
phylla (Raf.) Sarg.), and ponderosa pine (Pinus ponderosa
Laws.) seedlings showing that root quality, in terms of the
amount of fibrous roots, is closely related to field survival as
shown in table 3. Seedlings with large diameters (greater than 4
millimeters)
4 
usually survive better than smaller seedlings (less
than 4 millimeters), but this is partially related to the fact that
as average seedling diameter increases the absolute size of the
root system increases. For seedlings with the same root collar
diameter, the amount of roots can be an important factor
affecting survival, as shown in table 3. However, root system
size alone, within a given diameter class, does not appear to be
directly related to long-term growth in the field (2).
There is good evidence that these observations are relevant
to southern pines. It is known from field studies (figure 4) that
increased root development can be related to increased field
survival of southern pines (17,28,15,19,11,35). The relationship
is consistent enough to expect that practices which favor better
developed or more fibrous root systems (e.g. undercutting or
wrenching, lower seedbed densities, mycorrhizae enhance-
TABLE 3. PREDICTED THIRD YEAR SURVIVAL PERCENT FOR SELECTED
SEEDLING DIAMETERS AND ROOT CLASSES OF DOUGLAS-FIR UNDER
AVERAGE AND SEVERE PLANTING CONDITIONS BASED UPON
RESULTS FROM 14 SEPARATE FIELD EXPERIMENTS (3)
Root Planting Diameter range (mm)
quality' condition
2  
2-3 3-4 4-5 5-6 6-7
Pt. Pet Pet Pet. Pet.
Good average 75 81 83 87 88
severe 47 64 70 83 86
Medium average 64 75 79 82 87
severe 13 46 57 67 82
Poor average 31 60 70 77 83
severe 00 00 30 51 71
'Classification based on relative root mass within a diameter class.
2
Severe exposure is characterized by south facing aspects with slopes over 15
percent.
Survival at 2nd year, %
90
80-
70
60
50
40
30-
3 0 ' I I I I I I I I I I I I I
0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Average seedling root 
weight, g
FIG. 4. The relationship between root weight and seedling survival
for loblolly pine (17).
ment, careful lifting and handling, etc.) will result in better sur-
vival. In contrast, practices which result in smaller root systems
can result in reduced survival. For example, the pruning of
roots by tree planters can improve the ease of planting (when
making a small hole with a dibble or hoedad), but can reduce
outplanting survival (23). In addition, the stripping of roots by
tree planters can cause a reduction in new root growth (34) and
result in poor survival (20).
It is not easy to determine a single direct causal relationship
between root development and survival. There is substantial
research showing that the initiation of new roots following
planting is positively related to the initial size of the root system
(7,1,40,41) and new root growth is important for seedling sur-
vival. It also is known that potential water uptake is related to
the initial size of the root system in pine seedlings (7,27). Until
new roots develop, the existing root system must provide for
most of the water uptake. These older roots generally have
lower surface hydraulic conductivity and therefore total water
uptake is dependent on the size of the root system.
Furthermore, the larger the root surface area, the greater the
opportunity for creating adequate root to soil contact.
What is the minimum acceptable and the optimum desir-
able root morphology for bareroot southern pine? A root sys-
tem which is adequate to support the transpiration of the
seedling during establishment meets these criteria. Obviously,
the weather following planting is important, as is the initial
moisture content of the soil near the roots. Transpiration
potential depends heavily on the foliage surface area, which is
directly related to the size of the seedlings. This implies a need
for a favorable root-weight ratio (greater than 0.28), where the
ratio expresses the relative dry mass of the root to that of the
entire seedling.
Morphologically improved loblolly pine seedlings normally
have a several fold larger average root volume or mass than
Grade 3 seedlings (7,33,4). An acceptable root system for a
morphologically improved loblolly pine or slash pine seedling,
which will do well under a wide range of conditions, will have a
root volume greater than 3 cubic centimeters, and the dry
weight will be in the range of 0.8 to 
1.4 grams
5 
(the optimum
might be closer to 2 grams). The fresh weight of roots from a
4One-inch equals approximately 25 mm.r T.
morphologically improved longleaf pine seedling can exceed 10
grams.
PLANTER PRODUCTIVITY CONSIDERATIONS
When individuals compare different planting systems, they
do not often recognize that planting specifications have a major
impact on planter productivity (e.g. 10). For example, in both
the South and Pacific Northwest, federal planting costs are
often 50-100 percent greater than those of industry under simi-
lar site conditions. However, on comparable sites survival is
usually no different, probably because the additional specifica-
tions or planting regulations rarely provide a marginal improve-
ment in the conditions affecting seedling survival. Variation in
planting rates and costs among private landowners also reflect,
in part, the differences in planting specifications and the
degree of enforcement. Poor hand planting specifications and
lax crew supervision in the South have traditionally been the
non-industrial landowner's nemesis.
In addition to the planting specifications and site conditions,
the average size of the root system will affect planter productiv-
ity, as shown in figure 5. The consequence of this is a tendency
for planters to strip roots, discard larger seedlings, or open a
hole which is less than adequate to accommodate the roots.
Figure 5 illustrates the average effect that root system size,
characterized by the absolute mass of the roots, has on average
planter productivity. Lower productivity results from a combi-
nation of factors. The major impact occurs from the additional
effort needed to actually plant seedlings with larger root sys-
tems so that the same planting specifications are achieved.
A reasonable set of planting specifications includes scalping
organic debris away from the immediate location of the plant-
ing spot, opening a hole sufficient to accommodate the roots,
placing the root system deep into the soil, and firmly packing
moist mineral soil around the roots. Given similar planting
quality standards, how might planting techniques or tools affect
productivity? The highest rates reported using shovels are
about 2,000 trees per man-day with 2+0 stock (38), and about
1,800 trees per man-day with large Douglas-fir transplants on
friable loamy soils (personal observations) in Washington.
These are less than the 3,000 trees per man-day commonly
observed with hoedad crews planting morphologically unim-
Production, trees/man-hr.
200
190 
Composite equation
R
2 
= 0.70 n = 57
180 -
170 -
160 -
150 -
140 -
120 - + Average root mass 2.1 g
110 -
Low Moderate High
Planting difficulty
FIG. 5. The effect of root mass (dry weight) and planting difficulty on
planting productivity of Douglas-fir seedlings in central Washington.
proved seedlings on well prepared ground in the South, but
similar to the maximum rates for dibble bar planting.
While it is frequently stated that planting with shovels will
reduce planter productivity by approximately 20 to 30 percent
(compared to hoedads and in some cases dibble bars), there is
no good database to support this claim. Based on this estimate
some contractors have been reluctant initially to work with
shovels. Yet, contract prices on the west coast for crews work-
ing primarily with shovels have been as competitive as those
with hoedads. In addition, the results of an extensive study of
planter productivity showed no indication that average produc-
tion was less with shovels when compared to hoedads under a
wide range of conditions, as shown in figure 6. These studies
covered all types of soil texture and surface debris conditions
with the exception of clay and clay loam soils. In British
Columbia, Brown (5) also reported no differences in productiv-
ity between hoedads and shovels for seedlings with large root
systems.
The technique involved and ergonomics of shovel planting
are different than for other planting tools. Some contractors
have reported a lower incidence of worker injury with shovel
planting as compared with planting with hoedads. Planter pro-
ductivity depends heavily upon the individual's capacity and
training with the planting implement under a given set of spec-
ifications, site conditions, and root system size. Consequently,
comparisons among techniques and equipment are best
accomplished under standard conditions with professional
planters experienced enough to maximize performance. The
best combination of planting stock, specifications, and equip-
ment can be determined only by evaluating the cost effective-
ness of the system as a whole.
Production, trees/man-hr.
200
190
180
170
160
150
140
130
120
110
-- Hoedad contractor A (R
2 
= 0.47)
-.- Hoedad contractor B (R
2 
= 0.93)
o- Hoedad contractor C (R
2 
= 0.87)
-- All shovel units (R
2
= 0.86)
I I I I 1
0 5 10 15 20 25 30 35 40
Planting difficulty index
FIG. 6. The effect of planting difficulty on planting productivity with
contractors using hoedads and shovels. Planting difficulty index is
a function of (1) depth of surface debris; (2) amount of logging
residue; (3) slope; (4) amount of rock in surface soil; and (5) amount
of live woody roots in soil.
The planting difficulty index is determined by the formula:
index = 1.8*duff + 0.9*walk + 1.8*soil
where: duff = 1 + surface organic layer in cm
walk = (1 + logging residue in tonslacre)*(1 + % slope)
10 10
soil = (1 + % gravel content) * root score
10
root score = amount of root mat in soil surface
(1 = none; 2 = light; 3 = medium; 4 = heavy)
LITERATURE CITED
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Performance of Loblolly Pine Seedlings Raised at Two
Nurseries. M.S. thesis, Va. Polytech. Inst. and State Univ.,
Blacksburg, Va. 1
24 
pp.
(2) BLAKE, J.I. 1987. The Impact of Seedling Diameter and Root
mass on the Performance of Douglas-fir (Pseudotsuga menziesii
(Mirb.) Franco) and Associated Conifers. Internal Report to the
Pacific Northwest. Forest. Indust., SilvaTech, Auburn, Ala. 70
PP.
(3) , L.D. TEETER, AND D.B. SOUTH. 1989. Analysis of
the Economic Benefits from Increasing Uniformity in Douglas-
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(4) BOYER, J.N. AND D.B. SOUTH. 1988. Loblolly Pine Seedling
Morphology and Production at 53 Southern Forest Nurseries.
Tree Planters' Notes 39(3):13-22.
(5) BROWN, R. 1982. Planting and Organizing the Planting Project.
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(eds.). Proc. Canadian Containerized Tree Seedling Symposium.
Dept. Environ. Canadian Forest Serv., Sault St. Marie, Ontario,
Canada.
(6) BRISSETTE, J.C. AND J.P BARNETI. 1989. Depth of Planting and
J-rooting Affect Loblolly Pine Seedlings Under Stress
Conditions. pp. 169-175 In: Proc. Fifth Biennial Southern
Silvicultural Research Conf., Memphis, Tenn. U.S.D.A. Forest
Service General Technical Report SO-74.
(7) CARLSON, W.C. 1986. Root System Considerations in the Quality
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(8) DIERAUF, T.A. 1984. Depth of Planting Study. Occasional Rep.
63, Va. Div. of Forestry, Charlottesville, Va.
(9) GRUSCHOW, G.F. 1959. Observations on Root Systems of
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(10) GULDIN, R.W. 1984. Site Characteristics and Preparation
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(11) HATCHELL, G.E. AND D.H. MUSE. 1990. Nursery Cultural
Practices and Morphological Attributes of Longleaf Pine Bare-
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Forest Service. Res. Pap. SE-277. 34 pp.
(12) HAY, R.L. AND F.W. WOODS. 1974. Root Deformation Correlated
with Sapling Size for Loblolly Pine. J. For. 72:143-145.
(13) HOBBS, S.D. 1982. Effect of Auger Planting on Survival and
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(14) HUNTER, S.C. AND T.E. MAKI. 1980. The Effect of Root Curling
on Loblolly Pine. South. J. Appl. For. 4(1):45-49.
(15) JORGENSEN, J.R. AND E. SHOULDERS. 1967. Mycorrhizal Root
Development Vital to Survival of Slash Pine Nursery Stock. Tree
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(16) KLAWITTER, R.A. 1969. Wind Damages Improperly Planted
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(17) LARSEN, H.S., D.B. SOUTH, AND J.M. BOYER. 1986. Root Growth
Potential, Seedling Morphology, and Bud Dormancy Correlate
with Survival of Loblolly Pine Seedlings Planted in December in
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(18) LITrLE, S. 1973. Survival, Growth of Loblolly, Pitch, Shortleaf
Pines Established by Different Methods in New Jersey. Tree
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(19) MARX, D.H., C.E. CORDELL, AND A. CLARK III. 1988. Eight-
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(20) AND G.E. HATCHELL. 1986. Root Stripping of
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(21) MASON, E.G. 1985. Causes of Juvenile Instability of Pinus radia-
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(23) AND D.B. SOUTH. 1991. Bareroot seedling culture.
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(24) MILLER, R.E. 1969. Can Auger Planting Improve Survival of
Douglas-fir Seedlings. USDA For. Serv., PNW Res. Note #99.
(25) MULLER, C. 1983. Loblolly Pine Seedling Survival Study, 1979-
80 and 1980-81 Planting Season. pp. 27-34. In Proc. 1982
Southern Nursery Confer., USDA For. Serv., Technical Publ.
R8-TP4.
(26) MULLIN, R.E. 1964. Influence of Planting Depth on Survival and
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(27) NAMBIAR, E.K.S. 1984. Significance of First-order Lateral Roots
on the Growth of Young Radiata Pine Under Environmental
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(28) ROWAN, S.J. 1987. Nursery Seedling Quality Affects Growth and
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(29) SANDS, R. 1984. Transplanting Stress in Radiata Pine. Aust. For.
Res. 14:67-72.
(30) SENIOR, M.T., AND A.E. HASSAN. 1983. Field Evaluation of Tree
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Mich. 19 pp.
(31) SEILER, JR., D.J. PAGANELLI, AND B.H. CAZELL. 1990. Growth
and Water Potential of J-rooted Loblolly Pine and Eastern White
Pine Seedlings Over Three Growing Seasons. New Forests
4:147-153.
(32) SHIVER, B.D., B.E. BORDERS, H.H. PAGE JR., AND S.M. RAPER.
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(33) SOUTH, D.B., H.S. LARSEN, J.N. BOYER, AND H.M. WILLIAMS.
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(34) AND N.J. STUMPFF. 1990. Root Stripping Reduces
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(35) TANAKA, Y., J.D. WALSTAD, AND J.E. BORRECCO. 1976. The
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(36) URsIC, S.J. 1963. Modification of Planting Technique Not
Recommended for Loblolly Pine on Eroded Soils. Tree Planters'
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(37) WAKELEY, P.C. 1954. Planting the Southern Pines. USDA Agric.
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2 33 
pp.
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